12/28 | H5N1 not taking wing on migratory pathways - disease going by airplane

http://www.msnbc.msn.com/id/10624217/

Bird flu not taking wing on migratory pathways
Disease appears more likely to make its away around the globe by airplane
The Associated Press
Updated: 9:43 a.m. ET Dec. 28, 2005


WASHINGTON - Bird flu appears more likely to wing its away around the globe by plane than by migrating birds.
Scientists have been unable to link the spread of the virus to migratory patterns, suggesting that the thousands of wild birds that have died, primarily waterfowl and shore birds, are not primary transmitters of bird flu.
If that holds true, it would suggest that shipments of domestic chickens, ducks and other poultry represents a far greater threat than does the movement of wild birds on the wing.
It also would underscore the need to pursue the virus in poultry farms and markets rather than in wild populations of birds if a possible pandemic is to be checked, U.S. and European experts said.
The H5N1 strain has infected millions of poultry throughout Asia and parts of Europe since 2003. The virus also has killed at least 71 people, many of whom had close contact with poultry.
To date, the virus hasn’t been shown to spread from person to person, but many fear that it could mutate into a strain that could, potentially killing millions in a global pandemic.
While the prospect that migrating birds could carry the virus worldwide still worries health authorities, that sort of scenario doesn’t appear to be playing out.
“There is more and more evidence building up that wild migratory birds do play some role in spreading the virus, but personally I believe — and others agree — that it’s not a major role,” said Ward Hagemeijer, a wild bird ecologist with Wetlands International, a conservation group in Wageningen, Netherlands. “If we would assume based on this evidence that wild birds would be a major carrier of the disease we would expect a more dramatic outbreak of the disease all over the world.”
Reports this summer and fall of the spread of the H5N1 strain strongly suggested wild birds were carrying the disease outward from Asia as they followed migration patterns that crisscross the Earth. The timing and location of outbreaks in western China, Russia, Romania, Turkey and Croatia seemed to point to wild birds en route to winter grounds.
That put places like Alaska, where birds from the Old and New Worlds gather each summer to create what some call an “international viral transfer center,” on alert that the virus could arrive this coming spring. And from there, species like the buff-breasted sandpiper and others that split their time between North and South America could in theory transport the virus farther afield.
Since the early fall, however, there have been only scattered reports of more outbreaks. The disease has been glaringly absent, for example, from western Europe and the Nile delta, where many presumed it would crop up as migrating birds returned to winter roosts.
That suggests the strain has evolved to specifically exploit domestic poultry, whose short lives spent in tight flocks mean a virus has to skip quickly from bird to bird if it is to survive, said Hon Ip, a virologist with the U.S. Geological Survey’s National Wildlife Health Center in Madison, Wis.
That also means that while the virus can pass from domestic to wild birds, the latter may not be suited as transmitters of the strain — at least so far.
“By the timing of the spread and the pattern of outbreaks within a country and between countries, it does not make sense relative to a role for migratory birds as a means of spreading the virus,” Ip said.
For example, the virus killed thousands of bar-headed geese in May and June at Lake Qinghai in western China. The deaths raised immediate fears that the virus was on the move, jumping among hosts in the wild. In the Aug. 19 issue of the journal Science, scientists wrote that the virus “has the potential to be a global threat.”
But Ip and others suggest the lake is not as remote and pristine as initially portrayed, and that poultry raised in the area could have been the source of the flu strain that killed the geese.
“It is still patchy — the pattern of outbreaks — to really make a very definitive link between migratory birds and the disease,” said Marco Barbieri, the scientific and technical officer for the United Nations Environmental Program’s convention on migratory species in Bonn, Germany.
Experts caution that wild birds cannot be ruled out as future transmitters of the H5N1 strain, which has yet to be detected in North America. Migratory birds, for example, have been clearly implicated in the spread of West Nile virus, which has killed at least 762 people in the U.S. since 2002.
The H5N1 flu strain already is known to be lethal to nearly 60 species of birds; further mutations of the strain could allow it to infect many more. One of the latest victims is the Asian tree sparrow, according to a study published in the December issue of the Journal of Virology.
“The dogma right now is it is the waterfowl — ducks, sandpipers, gulls, plovers — essentially any bird that is water-associated,” said A. Townsend Peterson, a University of Kansas professor and curator of the school’s Natural History Museum and Biodiversity Research Center. “I will predict that that dogma will eventually fall by the wayside. I will guess that what we will eventually see is that avian influenza is much more widely distributed among birds and that land birds also play a significant role in the picture.”
That has made increasing the understanding of the migratory routes followed by birds more important than ever. It also draws attention to how little is still known about the routes.
The conventional maps that show flyways as fat arrows that can span continents and oceans lack the nuance and detail of how birds really move, including when and in what numbers, experts said. The maps also can gloss over how migratory patterns can vary among subspecies.
Traditional methods like bird watching and banding are helping flesh out the maps. And now tracking by satellite or radio, as well as genetic and isotopic sampling, are playing an increased role in sussing out the finer details of where birds travel and when.
In places like Alaska, where millions of individual birds representing more than 200 species arrive each spring, scientists readily confess the situation isn’t all clear.
“Fuzzy would be an operative word. We are in the process of defining the Alaskan migration system, and it is remarkably complex,” said Kevin Winker, curator of birds and an associate professor at the University of Alaska, Fairbanks.
In the United States, the U.S. Geological Survey, Fish and Wildlife Service and the Agriculture Department plan next year to step up their surveillance of wild flocks of birds.
In the past several weeks, scientists have winnowed down their list of birds they want to keep tabs on, said Dirk Derksen, a biologist with the USGS Alaska Science Center in Anchorage. All spend at least part of the year in Asia.
Early detection would buy time in forestalling the further spread of the virus — a situation no one wants.
“Initially, wild birds are primarily victims. Someday they may become vectors. We don’t know how that will play out,” Ip said. “What I would like to see is the virus stopped before it gets to America so we don’t see the last reel of this film played out in North America.”

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<B><center>December 28. 2005 6:59AM
<A href="http://www.southbendtribune.com/apps/pbcs.dll/article?AID=/20051228/Lives08/512280510/-1/LIVES/CAT=Lives08">South Bend Tribune</A>

<font size=+1 color=red>Bird flu spreads to Turkey, but don't panic</font>

Here are some facts about "bird flu,'' according to the Pan American Health Organization.

Avian influenza has killed tens of millions of chickens in five Asian countries, but human cases are rare, about 100 reported.</b>

It's unlikely that people will become infected from chicken in a grocery store or birds in their backyard.

When it does infect people, it's deadly; 70 of 100 have died.

The bird flu is spreading around the globe -- in birds -- and has been found in Greece, Romania and Turkey.

If it comes to birds in North America, it will still just be "bird flu'' and not the pandemic flu experts dread.

To become pandemic flu, bird flu would have to undergo a genetic mutation that makes it spread easily from person to person.

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<B><font size=+1 color=brown><center>Experimental treatments may be pandemic defense</font>

December 28 2005
<A href="http://www.theolympian.com/apps/pbcs.dll/article?AID=/20051228/NEWS/51228018/1001">The Olympian Online</a>
BY JEREMY MANIER
CHICAGO TRIBUNE</center>
CHICAGO — Despite recent moves by the federal government to build drug stockpiles for a possible outbreak of avian flu, some experts say the plans so far have neglected a key possibility: What if a pandemic strikes before the stockpiles are in place? </b>

Lung researchers at the University of Chicago believe doctors could turn to experimental therapies designed to prevent an infection from destroying the lungs. Rather than fight the virus itself, the drugs would dampen the immune system’s aggressive — and ulti-mately self-destructive — response to such viruses.

The approach would address what the University of Chicago team sees as potential weaknesses in the Bush administration’s proposal to purchase billions of dollars’ worth of flu vaccines and anti-flu medications such as Tamiflu. Those supplies will not be in place for several years, and the drugs might have limitations.

Last week, researchers from Vietnam reported that two bird flu patients had developed rapid resistance to Tamiflu and died.

The development underscored the need for other options in case anti-flu drugs such as Tamiflu and Relenza don’t work or the drugs are in short supply, said Dr. Steven Dudek, a pulmonary researcher at the University of Chicago.

“The drugs in our armament may not be as effective as people are hoping,” Dudek said.

“It would be nice to have some other way of treating people who get sick.”

Bird flu cannot spread among humans. But scientists fear it could mutate to acquire that ability and spiral into a worldwide pandemic. One solution might be drugs already being studied to treat other conditions that result in lung injury. Experts estimate that 80,000 people die each year from ailments that injure the lungs — most often infections with pneumonia, staph and other types of bacteria and viruses.

Stopping such lung injury in its tracks could reduce the pressing health threat posed by ordinary infections, in addition to addressing the still-theoretical risk of a flu pandemic, said Dr. Skip Garcia, chairman of the department of medicine at the University of Chicago.

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<B><font size=+1 color=red><center>Sifting Through Official Speak on Bird Flu</font>
by Jon Hamilton
December 28 2005
<A href="http://www.npr.org/templates/story/story.php?storyId=5071792">www.npr.org</a>



<font size=+1 color=blue>Human Bird-Flu Cases So Far</font></center>
Millions of birds in Asia have been slaughtered in an attempt to stop the spread of avian flu. Since 2003, there have been 141 cases of infection in humans, with 73 deaths.</b>

Cambodia: Reported its first outbreak of bird flu among poultry in 2003 and its first human case in 2005. It's had four confirmed human cases so far, all of them fatal.

China: Battled dozens of bird-flu outbreaks among poultry before confirming its first two cases in humans in November. Six human cases have been reported so far, two of them fatal. The most recent involved a 35-year-old man from Jiangxi province, who remains hospitalized; he was thought to have been infected through contact with sick ducks.

Indonesia: Most recent confirmed case involved an 8-year-old boy from Central Jakarta who died Dec. 15. The country has had 16 confirmed cases, all of them in 2005; 11 have been fatal.

Thailand: Most recent case of bird flu involved a 5-year-old boy who died Dec. 7. Results suggest the child was infected from dead chickens in his neighborhood in Nakhonnayok province. It was Thailand's second bird-flu death this year and its fifth confirmed case. Since 2004, Thailand has reported 22 cases, 14 of which have been fatal.

Vietnam: Identified its first human cases of bird flu in January 2004. Since then, the country has reported 93 human cases, 42 of them fatal.

-- Maria Godoy



Morning Edition, December 28, 2005 · Federal officials are saying some scary things about bird flu these days.

Earlier this month, for example, Health and Human Services Secretary Mike Leavitt said the virus that causes bird flu "could become one of the most terrible threats to life that this world has ever faced."

That's true. But it's hardly news. The current version of bird flu began infecting people back in 1997. Since then it's caused the deaths of about 150 million chickens and more than 70 people.

The most recent wave of bird flu began sweeping across Asia in 2003 -- long before the Bush administration began issuing a stream of dire warnings.

Risk communications expert Peter Sandman says that's not because the virus became more of a threat recently. Sandman says the change appears to be a response to criticism that the government wasn't prepared for another known threat: Hurricane Katrina.

"Prior to Katrina, the federal government in my judgment was profoundly over-reassuring about the risk of a pandemic," Sandman says. "Katrina had, I think, a lot to do with the federal government reversing its rhetoric and sounding much more alarming about pandemics."

Sandman and his wife, psychiatrist Jody Lanard, have done work on pandemic preparedness for the World Health Organization, the Centers for Disease Control and Prevention, and the Department of Health and Human Services. Sandman also works as a consultant on risk communications for a range of corporate clients.

Together they've written dozens of articles on how to communicate the risks associated with bird flu and other infectious diseases.

Lanard says her own interest in bird flu began well before the Bush administration started talking about it so publicly.

"I became concerned and then alarmed about pandemic influenza in about January 2004," she says, "while Thailand was still covering up the very obvious signs they had bird flu outbreaks in their poultry. I thought about what we should do. I thought about stockpiling food. I felt the fear of this thing spreading in Thailand."

Lanard spent months learning everything she could about the virus and its risks.


Lanard and Sandman say risk communicators must walk a tightrope. On one side is the risk of promoting irrational fear. On the other side is irrational complacency. The goal is to instill appropriate fear that gets people to take appropriate precautions.

Lanard says accomplishing this means presenting information that is accurate, complete, and often frightening.

"Good information should increase the level of fear in people that haven't been thinking about it at all," she says. "It should decrease the level of fear in people who are over-imagining how bad it could be."


Sandman and Lanard praise the Bush administration for finally sounding the alarm about pandemic flu. But they say the administration's message has been undercut at times by statements that are misleading, self-serving or simply wrong.

One example is an image federal officials frequently use to describe the pandemic.

In a speech at the National Institutes of Health, President Bush described it this way: "A pandemic is a lot like a fire, a forest fire. If caught early it might be extinguished with limited damage. If allowed to smolder undetected it can grow to an inferno that spreads quickly beyond our ability to control it."

Lanard says the forest fire image does capture the speed at which a pandemic can spread. But she says it's profoundly misleading to suggest that a flu pandemic can be snuffed out like a smoldering cigarette.

"The quote as it stands gives an overly optimistic impression of the likelihood of stomping it out," she says. "This has never been done. Surveillance is terrible in most of the developing world."

And even if someone did, scientists say it's far from certain the virus could be stopped.

Sandman says a better model for a pandemic might be a natural disaster like a tsunami -- or Hurricane Katrina.

"The vision of a natural disaster is not only that you can't prevent it," he says, "but that you can prepare for it and if you prepare for it you will ameliorate its bad effects."

Sandman says government officials sometimes mix true statements with statements that are demonstrably false. HHS secretary Leavitt, for example, has said, "When it comes to a pandemic, we are overdue and under-prepared."

Sandman says it's true the U.S. isn't prepared. But he says it's nonsense to think that just because there hasn't been a flu pandemic since the 1960s, we are somehow overdue.

"There's a name for that," Sandman says. "It's called the gambler's fallacy. It's exactly like somebody who's playing the roulette wheel, who notices that number 17 hasn't come up all night and bets on 17 because 17 is overdue. And what any statistician would say is every spin of the roulette wheel is a new random event, so there is no sense at all in which we are overdue."

Sandman says if people believe the gambler's fallacy, they'll expect the risk of a pandemic to rise every year one doesn't arrive. That's not how it works.

He says they'll also tend to think that if a pandemic does arrive, the risk of another one has been reduced. That's not true either.

Sandman and Lanard say even some true statements can be misleading.

In describing his plan to prepare for bird flu, President Bush said, "We must protect the American people by stockpiling vaccines and antiviral drugs, and improve our ability to rapidly produce new vaccines against a pandemic strain."

Lanard agrees that the government should be doing exactly those things.

But she says they shouldn't be suggesting these measures will protect us -- at least not anytime soon. At the moment, there is no human vaccine against bird flu. And it's far from clear that antiviral drugs will offer people much protection.


Lanard says the president's message has another problem: "It's a passive message to the public. It's the government as big father. The government is going to take care of you. And that is not what the public needs to hear in order to provoke preparedness."

Sandman and Lanard say that in the short run, individuals can do far more than the government to protect themselves.

For example, he says, people can keep extra food in case a pandemic disrupts distribution systems. They can prepare to work from home, in case it becomes hazardous to be in contact with other people. They can learn proper hand washing techniques to keep from spreading the virus.

And Sandman says there's another reason for the government to involve the public in any bird flu preparations.

"Everything that's known about the psychology of fear tells us that people can tolerate more fear if there is something for them to do," he says. "So it's not just inaccurate for the government to imply that the government will take care of it. It's not only getting in the way of the public's beginning to take preparedness more seriously. It's getting in the way of the public's ability to endure the threat of the pandemic itself."

Sandman and Lanard say the government seems overly concerned about panicking the public. They say history shows that's not likely, and that the right information now would reduce the risk even more.

Lanard says the more a person knows, the more realistic they'll be about pandemic flu. She says that's certainly true for her.

"[Bird flu] is one of the main things I think about," she says. "But I don't lose sleep over it. I don't think that every new case that comes out of China is it. It's already settled in my mind as one of the risks in the world.

Lanard and Sandman say people need to think about bird flu the same way they think about other real risks, like car accidents, or cancer, or even another hurricane like Katrina.

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<B><font size=+1 color=green><center>City hospital's pandemic plan</font>

by Mike Laycock
December 28 2005
<A href="http://www.thisisyork.co.uk/york/news/YORK_NEWS_LOCAL1.html">thisisYork.co.uk</a></center>
PLANNING: Dr Louise Coole is leading a team of health professionals in preparing for an outbreak of avian flu in York and North Yorkshire

HOSPITAL chiefs are drawing up plans to isolate bird flu victims if a pandemic strikes York in 2006.</b>

They are also working with other agencies to keep as many flu patients as possible in their own homes - "unless they needed specific clinical interventions that could only be provided in this setting".

Despite this, York Hospital bosses believe they would have to train more staff to ventilate critically ill patients in intensive care if the illness takes grip.

Their comments come after recent warnings from the House of Lords science and technology committee that Britain is hopelessly unprepared for such a pandemic - with a danger that the NHS might collapse under the weight of demand.

Senior Government scientists said in the autumn it was only a matter of time before a pandemic of avian flu hit Britain and Dr Louise Coole, consultant in communicable diseases at North Yorkshire Health Protection Unit, said then that "thorough and ongoing" contingency plans were being prepared to ensure the authorities locally were in the best possible position to respond to an outbreak.

Asked today what was being done at York Hospital to prepare for the worst, York Hospitals NHS Trust sought to reassure the public that it was continuing to work hard on "robust contingency measures to safeguard their health and wellbeing" in the event of a flu pandemic.

"This includes working closely with our partnership agencies - for example, local authorities, primary care organisations and hospitals - to address how people would receive care in their own homes, so they wouldn't need to go into hospital if there was a flu pandemic, unless they needed specific clinical interventions that could only be provided in this setting," said a spokeswoman.

"It is essential our contingency work focuses on preventing those people who are not emergency cases from being hospitalised."

She said this meant ensuring they got access to the best possible care in their own homes, so that hospital beds were freed up for people needing emergency treatment.

She said the trust was putting plans together for the hospital's accident and emergency department and wards to map out how patients with suspected flu would be isolated from other patients.

"We are also evaluating how many critically ill patients with symptomatic flu would need to be ventilated (intensive care unit support), so we can make the appropriate provision," she said.

"The need to ventilate more patients during a flu pandemic also means training more staff, to support our existing staff, when carrying out intensive care procedures."

She said the main day-to-day running of the hospital would follow usual operational arrangements in place during winter. "This means managing services on a daily basis to ensure emergency cases are treated as a priority."

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<B><font size=+1 color=blue><center>WHO warns of Avian flu epidemic</font>

December 27 2005
<A href="http://www.pakistanlink.com/Headlines/Dec05/27/05.htm">PakistanLink</a></center>
KARACHI, Dec 27 : The World Health Organization has warned of a substantial risk of an Avian Influenza epidemic in near future. One of the primary concerns is that the virus could quickly spread across countries as various birds follow their migratory routes.</b>

In response countries have began planning in anticipation of an outbreak. Vaccines that can be effective against a pandemic are still not available.

Health Ministry in Pakistan has also taken some precautionary measures against the Bird Flu, including ban on imports of birds from effected countries. The virus does not survive high temperatures and ours being a hot country the threat is not much. The tradition of food being cooked at high temperatures in our country is a plus point as it keeps us safe from such viruses.

However, the steps taken by the government have been much substantial, and a lot more can be done to gain maximum protection from the deadly disease. To begin with we need to have a proper waste disposal, hygienic transportation and storage of birds to create vaccines to prevent the outbreak.

Health experts have advised to increase use of antibacterial soaps and liquids, especially for those who have any contact with birds. This helps in minimizing the chances of the germs from spreading in human body, and staying clean and safe.

The most important fact is that Bird Flu is not yet a big threat, but it can be.

The current outbreaks of highly pathogenic Avian Influenza, which began in South East Asia are the most severe on record and have spread in a large number of countries all around the world. This outbreak has resulted in death of an estimated 150 million birds, causing major economic and social consequences.

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<B><font size=+1 color=purple><center>Outbreak of bird flu registered in 2 southern Russian regions</font>

28.12.2005, 18.28
ITAR-TASS</a></center>
MOSCOW, December 28 (Itar-Tass) - Russia’s Federal Service for Veterinary and Phitosanitary Control has registered an outbreak of bird flu in two southern territories – the Astrakhan region and the Republic of Kalmykia, the press service of the Agriculture Ministry said.</b>

As of December 28, the two territories had at least one population center each where bird flu had been detected.

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<i>Here is another version of Signwatcher's key article for this thread. It would appear (from the number of articles [more than 20 of them] on my news sourse sites) - that this is a big <b>Dot!</b></i>

<B><center>Dec 28, 2005 9:59 am US/Central
<A href="http://wfrv.com/topstories/local_story_362110728.html">CBS 5 Green Bay: Wisconsin</a>

<font size=+1 color=purple>Migratory Patterns Not Key In Bird Flu Spread</font></center>
(AP) WASHINGTON Bird flu appears more likely to wing its away around the globe by plane than by migrating birds.</b>

Scientists have been unable to link the spread of the virus to migratory patterns, suggesting that the thousands of wild birds that have died, primarily waterfowl and shore birds, are not primary transmitters of bird flu.

If that holds true, it would suggest that shipments of domestic chickens, ducks and other poultry represents a far greater threat than does the movement of wild birds on the wing.

It also would underscore the need to pursue the virus in poultry farms and markets rather than in wild populations of birds if a possible pandemic is to be checked, U.S. and European experts said.

The H5N1 strain has infected millions of poultry throughout Asia and parts of Europe since 2003. The virus also has killed at least 71 people, many of whom had close contact with poultry.

To date, the virus hasn't been shown to spread from person to person, but many fear that it could mutate into a strain that could, potentially killing millions in a global pandemic.

While the prospect that migrating birds could carry the virus worldwide still worries health authorities, that sort of scenario doesn't appear to be playing out.

"There is more and more evidence building up that wild migratory birds do play some role in spreading the virus, but personally I believe -- and others agree -- that it's not a major role," said Ward Hagemeijer, a wild bird ecologist with Wetlands International, a conservation group in Wageningen, Netherlands. "If we would assume based on this evidence that wild birds would be a major carrier of the disease we would expect a more dramatic outbreak of the disease all over the world."

Reports this summer and fall of the spread of the H5N1 strain strongly suggested wild birds were carrying the disease outward from Asia as they followed migration patterns that crisscross the Earth. The timing and location of outbreaks in western China, Russia, Romania, Turkey and Croatia seemed to point to wild birds en route to winter grounds.

That put places like Alaska, where birds from the Old and New Worlds gather each summer to create what some call an "international viral transfer center," on alert that the virus could arrive this coming spring. And from there, species like the buff-breasted sandpiper and others that split their time between North and South America could in theory transport the virus farther afield.

Since the early fall, however, there have been only scattered reports of more outbreaks. The disease has been glaringly absent, for example, from western Europe and the Nile delta, where many presumed it would crop up as migrating birds returned to winter roosts.

That suggests the strain has evolved to specifically exploit domestic poultry, whose short lives spent in tight flocks mean a virus has to skip quickly from bird to bird if it is to survive, said Hon Ip, a virologist with the U.S. Geological Survey's National Wildlife Health Center in Madison, Wis.

That also means that while the virus can pass from domestic to wild birds, the latter may not be suited as transmitters of the strain -- at least so far.

"By the timing of the spread and the pattern of outbreaks within a country and between countries, it does not make sense relative to a role for migratory birds as a means of spreading the virus," Ip said.

For example, the virus killed thousands of bar-headed geese in May and June at Lake Qinghai in western China. The deaths raised immediate fears that the virus was on the move, jumping among hosts in the wild. In the Aug. 19 issue of the journal Science, scientists wrote that the virus "has the potential to be a global threat."

But Ip and others suggest the lake is not as remote and pristine as initially portrayed, and that poultry raised in the area could have been the source of the flu strain that killed the geese.

"It is still patchy -- the pattern of outbreaks -- to really make a very definitive link between migratory birds and the disease," said Marco Barbieri, the scientific and technical officer for the United Nations Environmental Program's convention on migratory species in Bonn, Germany.

Experts caution that wild birds cannot be ruled out as future transmitters of the H5N1 strain, which has yet to be detected in North America. Migratory birds, for example, have been clearly implicated in the spread of West Nile virus, which has killed at least 762 people in the U.S. since 2002.

The H5N1 flu strain already is known to be lethal to nearly 60 species of birds; further mutations of the strain could allow it to infect many more. One of the latest victims is the Asian tree sparrow, according to a study published in the December issue of the Journal of Virology.

"The dogma right now is it is the waterfowl -- ducks, sandpipers, gulls, plovers -- essentially any bird that is water-associated," said A. Townsend Peterson, a University of Kansas professor and curator of the school's Natural History Museum and Biodiversity Research Center. "I will predict that that dogma will eventually fall by the wayside. I will guess that what we will eventually see is that avian influenza is much more widely distributed among birds and that land birds also play a significant role in the picture."

That has made increasing the understanding of the migratory routes followed by birds more important than ever. It also draws attention to how little is still known about the routes.

The conventional maps that show flyways as fat arrows that can span continents and oceans lack the nuance and detail of how birds really move, including when and in what numbers, experts said. The maps also can gloss over how migratory patterns can vary among subspecies.

Traditional methods like bird watching and banding are helping flesh out the maps. And now tracking by satellite or radio, as well as genetic and isotopic sampling, are playing an increased role in sussing out the finer details of where birds travel and when.

In places like Alaska, where millions of individual birds representing more than 200 species arrive each spring, scientists readily confess the situation isn't all clear.

"Fuzzy would be an operative word. We are in the process of defining the Alaskan migration system, and it is remarkably complex," said Kevin Winker, curator of birds and an associate professor at the University of Alaska, Fairbanks.

In the United States, the U.S. Geological Survey, Fish and Wildlife Service and the Agriculture Department plan next year to step up their surveillance of wild flocks of birds.

In the past several weeks, scientists have winnowed down their list of birds they want to keep tabs on, said Dirk Derksen, a biologist with the USGS Alaska Science Center in Anchorage. All spend at least part of the year in Asia.

Early detection would buy time in forestalling the further spread of the virus -- a situation no one wants.

"Initially, wild birds are primarily victims. Someday they may become vectors. We don't know how that will play out," Ip said. "What I would like to see is the virus stopped before it gets to America so we don't see the last reel of this film played out in North America."

Latest issue of the Smithsonian magazine has a good article on a famous virologist in the US and his serious lifetime work including avian flu.

Check it out.